In the past, there have been many educational devices which utilized the exterior surface of a sphere onto which jigsaw puzzle pieces were magnetically placed or otherwise affixed to illustrate global geography. An example is U.S. Pat. No. 3,618,955. Also, there have been educational devices which utilized the interior surface of a sphere or the interior surface of a hemisphere onto which celestial indicia were either painted, printed or otherwise graphically reproduced. An example is U.S. Pat. No. 3,046,677.
However, so far as is known to the present inventor, there have been no previous educational devices which utilized the concave interior surface of a hemisphere onto which jigsaw puzzle pieces bearing celestial indicia have been removably affixed to illustrate celestial spatial relationships.